As a packaging material for seal-packaging various articles such as foods, pharmaceutical and medical products, electronic parts and stationeries, there has been used a bag having a reclosable tape (reclosable-tape-having bag). As such a reclosable-tape-having bag, there has been known a bag that is obtained, for example, by heat-sealing a periphery of superposed packaging materials, heat-sealing a male fastener to an inner surface of one packaging material and a female fastener to an inner surfaces of the other packaging material along a bag opening periphery, and by adhering both the packaging materials at tip ends of the opening periphery.
The reclosable-tape-having bag is initially opened by ripping the tip ends of the bag opening periphery to take out a content, and the reclosable-tape-having bag is resealable and reopenable by fitting the male fastener with the female fastener thereafter.
Manufacturing of such a reclosable-tape-having bag entails operations firstly to seal the male fastener to one packaging material and the female fastener to the other packing material and subsequently to seal the periphery of the packaging materials for obtaining a bag product. However, when sealing positions of the male fastener and the female fastener to the packaging materials are even slightly misaligned, both the fasteners of the bag product are not well fitted with each other, which may lead to not only high cost due to an increase of defective products but also a complexity of manufacturing operations.
In order for the reclosable-tape-having bag to exhibit its function, an upper portion of the sealed bag (in immediate proximity to the reclosable tape) needs to be opened, and a user often opens the upper portion of the sealed bag by reference to a notch provided at a side seal of the bag. However, it is highly difficult to open the bag by hands levelly along a dotted line printed on the bag. For instance, a cutting line in opening the bag may be curved to cut off the upper portion of the bag in a middle or to conflict with the reclosable tape, whereby a resealing capability of the reclosable tape may be impaired. Thus, a scissors mark are often printed on the bag, thereby recommending the bag be opened using scissors.
However, it may impair a user's convenience to require the user to use the scissors every time the user opens the reclosable-tape-having bag. In addition, there is a limit to improve a cuttability by selecting a film material that forms the bag.
For solving the above-described problems, there has been suggested a reclosable-tape-having bag including an open tape in which a male fastener and a female fastener are attached in engagement to either of packaging materials (e.g., Patent Document 1). FIG. 12 is a front view schematically showing the reclosable-tape-having bag 500 in the vicinity of an opening trigger 550 in accordance with the Patent Document 1, and FIG. 13 shows a cross-sectional view taken along XIII-XIII line in FIG. 12.
The reclosable-tape-having bag 500 shown in FIGS. 12 and 13 is arranged such that a periphery is heat-sealed to form a side seal 600, and that an upper film 501, a male fastener 502, a female fastener 503 (a convex portion 502a of the male fastener is fitted with a concave portion 503a of the female fastener 503), a cut-off portion 504 (open tape 504) and a lower film 505 are integrated. As shown in FIG. 13, a tab 506 is provided to the side seal 600. When the bag is opened, the tab 506 and the cut-off portion 504 continuously connected with the tab 506 are pulled upward, such that the upper film 501 is simultaneously pulled up to be ripped off.
[Patent Document 1] Japanese Patent No. 2,749,886 ([Claims], [FIG. 1] to [FIG. 8])